Valis X: Yuko - Mou Hitotsu no Sadame

Valis X: Yuko - Mou Hitotsu no Sadame is the first chapter of the episodic Valis X .

The common story of the five episodes of Valis X is based on the events depicted in various installments of the Valis series, describing the adventures of a Japanese teenage girl Yuko Asou and her friends in a parallel world named Vecanti, where she fights its evil tyrants with the legendary sword of Valis. However, the episodes do not follow the plots of the individual games; rather, they tell the over-arching story of the entire series their own way, liberally mixing locations, characters, events, etc., and adding new sub-plots.

The first four chapters describe the same events from the point of view of four different characters; the final episode concludes the story.

In the first chapter, the protagonist is Yuko Asou, the main heroine of the series. She and her best friend Reiko are mysteriously transported to Vecanti, where they meet the local warriors, Valna and Cham, and together try to overthrow the tyrant Rogles and his successor Megas.

All the episodes have the same graphical style and identical gameplay system. Unlike the original Valis series, the episodes of Valis X are "visual novels", composed of text and still images; interactivity is confined to occasionally making a decision, which will slightly alter the following events (usually of sexual nature), without influencing the general story.

All the episodes of Valis X have large amounts of explicit sex scenes, mostly revolving around lesbian sex and depictions of the heroines being raped by tentacle monsters.